1. Technical Field
The present disclosure relates generally to an individual lighting control apparatus and method and, more particularly, to an apparatus and method for controlling the state of lighting based on the state, location and surrounding environment of a terminal that is being used by an individual.
2. Description of the Related Art
Visible light is light having a wavelength in the range visible to the human eye among electromagnetic waves. The wavelength ranges from 380 to 780 nm. In visible light, a variation in characteristics attributable to a difference in wavelength is exhibited in the form of color, and the wavelength decreases across the spectrum from red to violet. Light having a wavelength longer than that of red color is referred to as infrared light, and light having a wavelength shorter than that of violet is referred to as ultraviolet light. In the case of monochromatic light, 700˜610 nm corresponds to red, 610˜590 nm corresponds to orange, 590˜570 nm corresponds to yellow, 570˜500 nm corresponds to green, 500˜450 nm corresponds to blue, and 450˜400 nm corresponds to violet. A variety of colors can be represented by mixing colors having these wavelengths.
Visible light is visible to humans, unlike infrared light or ultraviolet light. Illumination which emits visible light should satisfy a variety of requirements such as accurate color representation. One of these requirements is little flickering. Since humans cannot perceive 200 or more flickers per second, illumination apparatuses using Light Emitting Diodes (LEDs) having fast flicker performance control flickering using Pulse Width Modulation (PWM) in order to increase the lifespan thereof and save energy.
Communication technology using light includes Infrared Data Association (IrDA) using the infrared range, VLC using visible light, and optical communication using optical fiber.
Although the Infrared Data Association (IrDA) is a nongovernmental standard organization that was found in 1993 to establish standards for infrared data communications, IrDA also refers to the communication standards established by the IrDA. Principal standards for PC personal computers include IrDA1.0 for a maximum data transmission speed ranging from 2.4 to 115.2 kbps and IrDA1.1 for maximum data transmission speeds of 1.152 Mbps and 4 Mbps. IrDA is technology for performing communication using a wavelength in the infrared range from 850 to 900 nm.
VLC is a wireless communication technology using a wavelength in the range of 380 nm to 780 nm. The visible light communication standardization process is being conducted within the IEEE 802.15 Wireless Personal Area Network (WPAN) Working Group. In Korea, the Telecommunications Technology Association (TTA) is operating a visible light communication working group.
For example, Korean Patent Application Publication No. 10-2011-0031082 entitled “VLC Method and Apparatus capable of Controlling Brightness of Light Source while Minimizing Reduction in Brightness of Light Source” discloses technology that is capable of, when a VLC transmission function is provided to a lighting device or a visual light source, controlling the brightness of the lighting device or the visual light source while minimizing a reduction in the brightness of the lighting device or the visual light source which is generated by communication coding and modulation functions.
However, although the conventional lighting control technology is used to control the brightness of a lighting device or a light source within a set area or a corresponding area, there is a need for individual user-centric lighting control technology that will be more efficient in terms of energy conservation.